1. Technical Field
The present disclosure relates to an electrolyte composition for a dye-sensitized solar cell (DSSC).
2. Description of Related Art
A dye-sensitized solar cell (DSSC) is recognized as one of the new generation solar cells for advantages like simple processing, easy mass production and low cost. Generally, the DSSC includes an anode, a semiconductor layer (e.g., a titanium dioxide layer), dye, a counter electrode and electrolyte. The electrolyte is used to transfer holes to the counter electrode, such that the ion conductivity of the redox couple would have critical influence on the photoelectric conversion efficiency of the DSSC. In addition, the electrolyte ideally requires the features of low volatility, less leakage and easy packaging.
In order to meet the requirement of the electrolyte on low volatility and less leakage, researchers developed a wide range of electrolyte compositions. Taiwan (R.O.C) Patent Publication No. 201043662 provided a polymer-containing gel electrolyte, which may further include nanoparticles to increase the ion conductivity. Since the gel electrolyte has a certain viscosity, the sedimentation rate of the inorganic particles from the gravity can be slowed down. Nevertheless, the ion conductivity is thus decreased due to the viscosity of the gel electrolyte. Therefore, the transfer rate of the hole cannot be effectively increased so as not to increase the photoelectric conversion efficiency of the solar cell, even though the nanoparticles are added into the gel electrolyte. Concerning the type of liquid electrolyte, although liquid electrolyte exhibits high ion conductivity and electrode permeability, it is not suitable for adding nanoparticles therein to increase the ion conductivity for its high fluidity.
Accordingly, there is a need for an electrolyte composition having inorganic nanoparticles hard to subside, so as to increase the photoelectric conversion efficiency of the DSSC.